Collector ring brush



Patented Jan. ,31, 1933 UNITED STATES PATENT OFFICE FREDERICK P. FULLER,F YONKERS, NEW YORK COLLECTOR RING BRUSH No Drawing. Application filedFebruary 7, 1931. Serial No. 514,816.

This invention pertains to means for lubri- 6. An article of manufacturecomprising eating rubbing surfaces, particularly the a collector ringbrush composed in part of brushes and collector rings of rotaryconcalcium chloride. verters, induction motors, turbo-generators, Intestimony whereof I hereto afiix my sigand the like. nature.

Under certain conditions of service, partic- FREDERICK P. FULLER. ularlyunder certain weather conditions, the brushes are inclined todisintegrate or dust, and the collector rings are inclined to cut. Thebrushes are generally composed of a 55 lubricant, such as graphite,combined with metal, the combination being usually effected by fusion,by impregnation, or simply by mixing. The principal object of theinvention is to greatly reduce dusting of the brushes and cutting of therings by incorporatin in the brushes a hygroscopic materiahpre erabl asalt such as calcium chloride or any other suitable hygroscopic salt,whereby the brushes are enabled to absorb moisture from the atmosphereand thereb moisten and thereby aid in lubricating t e surface with whichthey come in contact. 25 In practice the regular brushes ma be replacedby brushes made according to t e present invention, or the re larbrushes may be left in place and sets 0 hygroscopic-brushes may beplaced in contact with the collector 0 rings or commutators between thesets of regular brushes.

I claim: 1. A brush comprising graphite in combination with ahygroscopic salt.

2. A brush comprising graphite in combination with calcium chloride.

3. A brush comprising lubricating conducting material in combinationwith a hygroscopic salt.

4. A brush comprising lubricating conductin material in combination withcalcium chlori e.

5. An article of manufacture comprising a collector ring brush composed,at least in 45 part, of hygroscopic salt.

